1. Field of the Invention
This invention relates to a locking device having a plurality of links, and more particularly to a locking device for securing objects of regular or irregular shape.
2. Prior Art
Many types of locks have been invented for various purposes. One such type is a U-shaped lock, as shown in FIG. 15, which includes a shackle having its respective ends insertable into a pair of corresponding apertures in a tubular member and locked by a lock mechanism. This lock has a rigid structure which can only be secured about an object which has an identical shape or which is smaller in size than the opening defined by the shackle. If the object to be secured has a larger size or has an irregular shape, the U-shaped lock is then useless.
A further prior art lock is a Bar Lock Linkage, U.S. Pat. No. 3,747,376, as shown in FIG. 16. Such consists of a bar lock having a plurality of bar links which are pivotally fastened together end to end by rivets. The bar lock has two free ends fastened together by a barrel lock. Each bar link is able to pivot relative to one another at the pivoted connections enabling the bar lock to be folded together into a compact package for storage purposes. But at least one acute angle is formed by a pair of the bar links when locking an object, and the acute angle may incidentally hurt someone.
Another prior art lock is a Bike Security Device, U.S. Pat. No. 3,784,876, as shown in FIG. 17. That device consists of three links, the first link extending a distance which is normally longer than the span between the wheels of a bicycle and having a pair of loops at respective ends adapted for articulated engagement with a second and a third link in a pivotal manner. This device utilizes a padlock to form a securing loop. The padlock is separate from the links and that requires them to be stored separately.
A fourth example of a prior art lock is a Ski Lock, U.S. Pat. No. 585,184, as shown in FIG. 18. The Ski Lock comprises a plurality of plates hinged together to form into a rectangular structure so as to surround a pair of skis disposed in bottom-to-bottom relationship. The end plates are locked together by a padlock with a chain surrounding a permanent fixture so that the skis cannot be stolen. The padlock is also separate from the plates and is required to be stored separately.
A fifth example of a prior art lock is a Wheel Lock, U.S. Pat. No. 4,760,718, as shown in FIG. 19. This type of lock comprises a plurality of rigid members being pivotally coupled to each other and having a lockable connection at the outer ends, so as to form a loop to lock a wheel to an associated fixed element. This device is limited by its space to secure objects. Furthermore, the linkage of such prior art locks is generally composed of a bolt A, as shown in FIG. 20, having a head A1 on top and a shank A2 which includes a larger section A21 and a smaller section A22. A pair of apertures C1, D1 are formed on lock rod C, and D respectively. The inner diameters of the apertures C1, and D1 are slightly larger than the larger section A21 so that the larger section A21 can insert through the apertures C1 and D1. The smaller section A22 will be exposed outward from the end opposite the head A1 and will be hammered flat to hold the bolt A in place, as shown in FIG. 21. Because of the hammering requirement, the bolt A is unable to be processed with heat treatment. This causes the bolt A to be easily broken by shear forces, as shown in FIG. 22.